Device for transferring liquids in vacuum



Feb. 27,1940. H. J. M CREARY DEVICE FOR TRANSFERRING LIQUIDS IN VACUUM' 2 Sheets-Sheet 1 O riginal Filed Sept. 20, 1935 Feb. 27, 194-0. MCCRIEARY I 2,192,140

DEVICE FOR TRANSFERRING LIQUIDS IN VACUUM Original Filed Sept. 20, 1935' 2 Sheets-Sheet 2 Patented Feb. 27, 1940 UNITED STATES DEVICE F OR 'TRANSFERRING LIQUIDS IN VACUUM Harold J. McCreary, Genoa, 111., assignor to Chicago Television & Research Laboratories, Inc., a corporation of Illinois Original application September 20, 1935, Serial No. 41,366. Divided and this application July 31, 1937, Serial No. 156,656

2 Claims.

The invention relates to a process for purifying dielectrics and is a division of my application filed September 20, 1935, under Serial i1,366.

It is an object of the invention to provide a novel device for transferring a liquid under A further object aims at providing means in 15 the second vacuum system but actuable from without, to establish communication between the vessel and the second vacuum system.

Other equally important objects will become 20 apparent from a perusal of the application commeans and the steps of the process employed in the invention, and from the claims which particularly point out the novel features of the invention. The means for carrying out the process constituting the invention is illustrated in the accompanying drawings, in which Figs. 1 and 2 illustrate the apparatus used in carrying out my invention.

Referring to the drawings, I is a Pyrex'glass tube approximately 1" in diameter and 3 ft. long, sealed at one end to a smaller tube 2 which is approximately 7 in diameter, and 3" long. Tubes I and 2 comprise the filtering column. A porcelain straining disc 3 is installed with a loose fit into the tube I and rests on the constricted portion 4 of the glass tube I. Five discs of filter paper 5 are rammed down on top of the porcelain strainer 3 by means of a glass tube (not shown) slightly smaller than the tube I. The filter paper discs are aboutv 4;" larger than the inside bore of tube I, and are pushed into place'one at a time. By this process the proper grade of strainer is installed in tube I.

Commercially pure calcium oxide 6 is finely powdered with a mortar and pestle and is then placed on top of the filter'paper discs 5. The

calcium oxide 6 is packed down with a glass rod (not shown) so'that it forms a column approximately, six inches deep in the tube I. Ontop of this column of calciumoxide two discs of filter paper I, exactly of the same type as filter paper 5, are rammed into place.

A column approximately long of tightly packed commercially pure anhydrous sodium sulphate 8 is then placed on top of the filter paprising the specification, which sets forth the per discs I. The sodium sulphate has been very finely powdered before using. The remainder of tube I is now filled withthe nitrobenzene to be purified and a loose fitting cover 9 is placed on top of the glass tube I to keep dust and other impurities out.

The filtering column I isconnected by means of a small tube 2 to the glass bulb II-which, in turn, is connected by a tube I2 to a residual container I3 and by a tube It to a special flask I5 through a seal-off iconstriction IS. The glass bulb II is also connected by tube It to an oil vacuum pump (not shown); The flask I5 is special in that it has in its'neck; IT a capillary I8 so that it can be opened in a vacuum in a manher well known in the art of handling rare gases. I.

Attention is called to the fact that the filtering column at the top has less vacuum than at the bottom, so that as the liquid descends it is subjected to a progressively increasing vacu- The entire glass structure comprising filtration column I, bulb II, residual container I3, and special flask I5, are all Welded into a continuous vacuum-tight envelope and mounted with clampsvon a tilting structure pivoted so that the envelope may be tilted so that either tube I2 or tube It may be filled with processed nitrobenzene from the tube 2 of the filtering column.

The glass structureof Fig. l is tilted on its pivot so that the aperture of tube 2 is .directly over the aperture of tubezIE. The oil vacuum pump connected to tube It with a rubber hose is started and the nitrobenzene which has been poured into the top of filtration column I will seep down the filtration column until it drips from the aperture of tube 2 into tube I2 and into the residual container I3.

After a few teaspoonsiul have dripped into the container I3, the glass structure is tilted about its pivot in such a manner that the nitrobenzene from tube 2 will drip into tube I l and run down into the special fiask I5. The top of the filtration column is always kept full of nitrobenzene and is never allowed to get down to the top surface of the sodium sulphate. When the special fiask I5 has been filled to within a short distance of the seal-off constriction It, the glass structure is tilted on its pivot until the nitrobenzene again drips into tube I2. The seal-01f constriction I6 is then warmedto vaporize the nitrobenzene on the inner surface, and the special flask I5 is then sealed offfl The special flask I5, which has been sealed 011? full of nitrobenzene, after completion of the operation just described, is inverted as shown in Fig. 2, and the neck I! is sealed to the-tube 20.

I 9a is a solenoid which is placed over the tube 20 before making the seal between the neck I! and the tube 20. 2| is an iron slug and 22 is a steel spring placed in a tube 20 before making the seal of tube H to tube 20. Ihe solenoid Illa is connected by a cord through a snap switch and connection plug to a IOU-volt D. C. source, the switch normally being in the 01f position. It will be observed that the tube 20 leads to a distilling flask 23, which is wrapped with asbestos rope 24 for heat insulation purposes. The flask 23 is also protected from air currents by an asbestos paper cylinder 25 placed at the bottom,

of the flask. An electrical heater 26 is placed in the bottom of the paper cylinder 25 and is connected to a 1l0-volt D. C. source through a rheostat 2'! and a connection plug 28. At the top of the neck of the distillation flask 2 is a thermometer Well 29 of glass and a close slidingflt for the thermometer 36. Mercury 3! is placed-in zene vapors to a condensing coil, not shown.

Energy is then connected to the magnet iQa,

- by inserting the energizing plug into a l10-volt D. C. source and operating switch 29. This action will cause iron slug 2| to strike capillary tube l8 and break it. The nitrobenzene will now flow down into the distillation flask 23.

When all of the nitrobenzene is in the flask 23 and the vacuum pumps have restored a good vacuum to the system, the heater 28 is started and adjusted so that it gradually brings the temperature up to about deg. centigrade. Both temperature and pressure should be maintained constantly during the distillation process. l

My invention is not limited to the particular arrangement of apparatus as shown in the drawings in carrying out the process, but may be vari- 1. In a device for purifying a dielectric, a vessel containing a dielectric under vacuum, said vessel having a projecting neck with a frangible seal thereacross spaced inwardly of the outer end of the neck, a vacuum system having a tube sealed withthe end of the neck of the vessel around the seal and longitudinally aligned with said neck, means mounted in said tube for movement longitudinally thereof into breaking engagement with the seal, and means externallyv of the tube actuating said breaking means.- 1

2. In a device for purifying adielectric, a v'essel containing a dielectric under vacuum, said vessel having a projecting neck with a, frangible seal thereacross spaced inwardly of the outer end of the neck, a vacuum system having a tube sealed with the end of the neck of the vessel around the seal and longitudinally aligned with said neck, a striker mountedin said tube for movement longitudinally thereof into breaking engagement with the seal, and an electro-magnet surrounding said tube externally thereof for actuating said striker. I

HAROLD-VJ. MCCREARY. 

